In the neutralization of 50.0 mL of 0.1 M BOH (a weak base with Kb = 1.6 × 10^-7) with 0.10 M H₂SO₄, the most correct description of the solution at the mid-point of the titration, i.e., half neutralized, is: A) a solution in which [B⁺] essentially equals [BOH] B) a solution in which [B⁺] essentially equals 4 × 10^-4 M C) a solution whose volume is 75 mL and contains some undissociated BOH molecules and some B⁺, OH^-, and HSO₄^- ions D) a solution containing SO₄^2- and B²⁺ ions E) a solution in contact with BSO₄ solid

Question

Quizplus · Accepted Answer

At the mid-point of the titration, half of the BOH has been neutralized by the added acid, leaving an equal amount of BOH and its conjugate acid, B+ in solution. Since BOH is a weak base, only a small fraction of it will be ionized, and thus [B+] will be essentially equal to [BOH]. Therefore, the solution will contain approximately equal concentrations of BOH and its conjugate acid, and the best choice is A.

In the Neutralization of 50